TECHNICAL FIELD
[0001] The present disclosure relates to an active gas generation apparatus having a parallel
plate type electrode structure and generating active gas using dielectric barrier
discharge.
BACKGROUND ART
[0002] In a conventional active gas generation apparatus with a parallel plate type electrode
structure in which a dielectric barrier discharge is adopted, a gap between a metal
electrode (electrode conductive film) and a dielectric film (electrode dielectric
film) facing each other or a gap between dielectric films facing each other serves
as a discharge space.
[0003] Adopted to the conventional active gas generation apparatus is a parallel plate type
dielectric barrier discharge in which a dielectric barrier discharge is generated
in a discharge space, and material gas injected in the discharge space is activated
to generate the active gas.
[0004] For example, an active gas generation apparatus disclosed in Patent Document 1 is
an example of an active gas generation apparatus in which the parallel plate type
dielectric barrier discharge is adopted.
[0005] The active gas generally has a short lifetime as active gas (a period of time during
which the active gas keeps high reactivity), thus the active gas needs to be supplied
to a space where the active gas is to be used in a short time. The active gas is also
inactivated when colliding with the other material, thus it is not preferable to supply
the active gas to a space where the active gas is used through a meandering pipe,
for example.
[0006] Thus, when a processed object (an object onto which the active gas is blown) is large
in a space where the active gas is used, a first improvement structure of providing
a gas ejecting hole for supplying the active gas to the space where the active gas
is to be used and a second improvement structure including a plurality of discharge
spaces corresponding to a plurality of gas ejecting holes, respectively.
PRIOR ART DOCUMENTS
PATENT DOCUMENT(S)
[0007] Patent Document 1: International Publication No.
2019/138456
SUMMARY
PROBLEM TO BE SOLVED BY THE INVENTION
[0008] A method of providing a plurality of through holes in one dielectric film is adopted
to the first improvement structure described above. Accordingly, the first improvement
structure has a problem that a size of the dielectric film needs to be increased in
accordance with the processed object, and a size of an apparatus configuration increases.
[0009] In addition, the first improvement structure also has a problem that there is no
mechanism of removing heat generated by discharge, and the dielectric film is broken
by heat generation by the discharge.
[0010] The second improvement structure described above has a problem that a size of an
apparatus configuration increases by reason that the plurality of discharge spaces
need to be provided.
[0011] In the active gas generation apparatus disclosed in Patent Document 1, when differential
pressure is applied to the dielectric film, measures such as increase in a thickness
of the dielectric film are necessary, and when the thickness of the dielectric film
is increased, necessary applied voltage increases. When the applied voltage is increases,
there is a problem that measures against insulation breakdown of an unnecessary portion
and steps of increasing a size of an introduced terminal are necessary to deal with
high voltage.
[0012] In addition, the conventional active gas generation apparatus disclosed in Patent
Document 1 has a problem that it has less cooling efficiency by reason that the dielectric
film is cooled by purge gas. Because, the conventional active gas generation apparatus
has a low heat removal ratio due to air cooling.
[0013] The present disclosure is to solve the above problems, and an object of the present
disclosure is to provide an active gas generation apparatus having a structure of
preventing insulation breakdown of at least a dielectric film.
MEANS TO SOLVE THE PROBLEM
[0014] An active gas generation apparatus according to the present disclosure is an active
gas generation apparatus activating material gas supplied to a discharge space to
generate active gas, comprising: an electrode unit; and a chassis housing the electrode
unit in a chassis space and having conductivity, wherein the chassis includes a chassis
bottom part including a flat surface and a conductor housing space concaved from the
flat surface in a depth direction, the electrode unit includes: a first electrode
constituting part; a second electrode constituting part provided on a lower side of
the first electrode constituting part; and a reference potential conductor provided
on a lower side of the second electrode constituting part and housed in the conductor
housing space, the first electrode constituting part includes a first electrode dielectric
film and a first electrode conductive film formed on an upper surface of the first
electrode dielectric film, the second electrode constituting part includes a second
electrode dielectric film and a second electrode conductive film formed on a lower
surface of the second electrode dielectric film, the reference potential conductor
includes an active gas buffer space on an upper portion, the second electrode constituting
part is disposed to cover the active gas buffer space, the second electrode dielectric
film includes a dielectric through port passing through the second electrode dielectric
film in a region overlapped with the active gas buffer space in a plan view, the second
electrode conductive film includes a conductive film opening part in a region overlapped
with the active gas buffer space in a plan view, the conductive film opening part
is overlapped with the dielectric through port in a plan view, the chassis bottom
part includes a gas flow path receiving material gas from an outer portion, a material
gas flow space is provided between the reference potential conductor and the conductor
housing space of the chassis, a space where the first electrode dielectric film and
the second electrode dielectric film face each other is defined as a main dielectric
space, the discharge space includes a main discharge space as a region in which the
first and second electrode conductive films are overlapped with each other in a plan
view in the main dielectric space, material gas is introduced into the discharge space
via the gas flow path and the material gas flow space, alternating-current voltage
is applied to the first electrode conductive film, the second electrode conductive
film is set to have reference potential via the chassis and the reference potential
conductor, the active gas generation apparatus further includes: a dielectric film
support member provided on the flat surface of the chassis and including a support
surface supporting the first electrode dielectric film from a lower side; and a dielectric
film suppression member for suppressing the first electrode dielectric film from an
upper side, the dielectric film suppression member not being overlapped with the first
electrode conductive film in a plan view, a lower surface of the dielectric film suppression
member includes a dielectric contact region having contact with an upper surface of
the first electrode dielectric film and a dielectric non-contact region not having
contact with an upper surface of the first electrode dielectric film, the dielectric
contact region is overlapped with a peripheral region of the first electrode dielectric
film and the support surface of the dielectric film support member in a plan view,
the dielectric non-contact region is overlapped with an intermediate region of the
first electrode dielectric film in a plan view, the intermediate region is a region
adjacent to a side of the first electrode conductive film from the peripheral region,
the dielectric film suppression member has conductivity and is set to have the reference
potential, and the first electrode dielectric film is suppressed by the dielectric
film suppression member from an upper side in the dielectric contact region.
EFFECTS OF THE INVENTION
[0015] In the active gas generation apparatus according to the present disclosure, the first
electrode dielectric film is suppressed by the dielectric film suppression member
from the upper side in the dielectric contact region. Thus, a region where load is
applied to the first electrode dielectric film by the dielectric film suppression
member can be limited to a lower region of the dielectric contact region.
[0016] As a result, the active gas generation apparatus according to the present disclosure
can fix the first electrode dielectric film between the dielectric contact region
of the dielectric film suppression member and the support surface of the dielectric
film support member without unnecessary bending stress applied to the first electrode
dielectric film.
[0017] Furthermore, the dielectric non-contact region of the dielectric film suppression
member set to have the reference potential and having conductivity is overlapped with
the intermediate region of the first electrode dielectric film in a plan view.
[0018] As a result, electrical field strength of the first electrode conductive film can
be reduced to reduce potential of the intermediate region of the first electrode dielectric
film, thus an electrode unit in the active gas generation apparatus according to the
present disclosure can prevent insulation breakdown in a gap between the first electrode
dielectric film and the dielectric film support member.
[0019] These and other objects, features, aspects and advantages of the present disclosure
will become more apparent from the following detailed description of the present disclosure
when taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF DRAWINGS
[0020]
[Fig. 1] A plan view schematically illustrating a planar structure of an active gas
generation apparatus as an embodiment 1 according to the present disclosure.
[Fig. 2] A cross-sectional view illustrating a cross-section structure of an A-A cross
section in Fig. 1.
[Fig. 3] An explanation diagram (No. 1) schematically illustrating a planar structure
of an electrode unit.
[Fig. 4] An explanation diagram illustrating a cross-section structure of a B-B cross
section in Fig. 3.
[Fig. 5] An explanation diagram (No. 2) schematically illustrating a planar structure
of the electrode unit.
[Fig. 6] An explanation diagram illustrating a cross-section structure of a C-C cross
section in Fig. 5.
[Fig. 7] An explanation diagram schematically illustrating a planar structure of a
chassis.
[Fig. 8] An explanation diagram schematically illustrating a planar structure of the
chassis.
[Fig. 9] An explanation diagram schematically illustrating a planar structure of a
high voltage side dielectric film.
[Fig. 10] An explanation diagram schematically illustrating a cross-section structure
of the high voltage side dielectric film.
[Fig. 11] An explanation diagram schematically illustrating a planar structure of
a ground side dielectric film.
[Fig. 12] An explanation diagram schematically illustrating a cross-section structure
of a ground side dielectric film.
[Fig. 13] An explanation diagram schematically illustrating a planar structure of
a power supply body.
[Fig. 14] An explanation diagram schematically illustrating a cross-section structure
of the power supply body.
[Fig. 15] An explanation diagram schematically illustrating a planar structure of
a ground conductor.
[Fig. 16] An explanation diagram schematically illustrating a cross-section structure
of the ground conductor.
[Fig. 17] An explanation diagram illustrating details of a focus region in Fig. 16.
[Fig. 18] An explanation diagram schematically illustrating a planar structure of
a cover dielectric film.
[Fig. 19] An explanation diagram schematically illustrating a cross-section structure
of the cover dielectric film.
[Fig. 20] An explanation diagram schematically illustrating a planar structure of
a ground side electrode constituting part.
[Fig. 21] An explanation diagram schematically illustrating a cross-section structure
of the ground side electrode constituting part.
[Fig. 22] An explanation diagram schematically illustrating a planar structure of
a shield dielectric film.
[Fig. 23] An explanation diagram schematically illustrating a cross-section structure
of the shield dielectric film.
[Fig. 24] An explanation diagram schematically illustrating a planar structure of
a dielectric film support member.
[Fig. 25] An explanation diagram schematically illustrating a cross-section structure
of a dielectric film support member.
[Fig. 26] An explanation diagram schematically illustrating a planar structure of
a dielectric film suppression member.
[Fig. 27] An explanation diagram schematically illustrating a cross-section structure
of the dielectric film suppression member.
[Fig. 28] An explanation diagram illustrating details of a focus region in Fig. 27.
[Fig. 29] An explanation diagram schematically illustrating a planar structure of
a press member.
[Fig. 30] An explanation diagram schematically illustrating a cross-section structure
of the press member.
[Fig. 31] A plan view schematically illustrating a planar structure of an active gas
generation apparatus as an embodiment 2 according to the present disclosure.
[Fig. 32] 1 A cross-sectional view illustrating a cross-section structure of a D-D
cross section in Fig. 31.
[Fig. 33] An explanation diagram schematically illustrating a planar structure of
a power supply body used in an electrode unit in an active gas generation apparatus
according to an embodiment 3.
[Fig. 34] An explanation diagram illustrating a cross-section structure of an E-E
cross section in Fig. 33.
[Fig. 35] An explanation diagram schematically illustrating a cooling function in
a basic configuration according to the embodiment 3.
[Fig. 36] An explanation diagram schematically illustrating a cooling function in
a modification example according to the embodiment 3.
[Fig. 37] An explanation diagram illustrating a cross-section structure of an electrode
unit in an active gas generation apparatus according to an embodiment 4.
[Fig. 38] An explanation diagram schematically illustrating a planar structure of
a high voltage side dielectric film illustrated in Fig. 37.
[Fig. 39] An explanation diagram schematically illustrating a cross-section structure
of the high voltage side dielectric film illustrated in Fig. 37.
DESCRIPTION OF EMBODIMENT(S)
<Embodiment 1>
[0021] Fig. 1 is a plan view schematically illustrating a planar structure of an active
gas generation apparatus 71 as an embodiment 1 according to the present disclosure.
[0022] As illustrated in Fig. 1, three electrode units 51 to 53 are housed in a chassis
1 in the active gas generation apparatus 71. Material gas G1 is supplied to each of
the electrode units 51 to 53 through a gas flow path 21. Each of the electrode units
51 to 53 activates the material gas G1 supplied to a discharge space 4 to generate
active gas G2.
[0023] Fig. 2 is a cross-sectional view illustrating a cross-section structure of an A-A
cross section in Fig. 1. Fig. 3 to Fig. 6 are explanation diagrams each partially
illustrating a structure of an electrode unit 50. The electrode unit 50 corresponds
to any of the electrode units 51 to 53. The electrode units 51 to 53 have the same
structure as each other.
[0024] Fig. 3 is an explanation diagram schematically illustrating a planar structure of
the electrode unit 50. Fig. 4 is an explanation diagram illustrating a cross-section
structure of a B-B cross section in Fig. 3. Each of Fig. 3 and Fig. 4 is a first explanation
diagram illustrating a structure of a ground conductor 6 and an area around the ground
conductor 6.
[0025] Fig. 5 is an explanation diagram schematically illustrating a planar structure of
the electrode unit 50. Fig. 6 is an explanation diagram illustrating a cross-section
structure of a C-C cross section in Fig. 5. Each of Fig. 5 and Fig. 6 is a second
explanation diagram illustrating a detailed structure of the ground conductor 6 and
the area around the ground conductor 6.
[0026] Fig. 7 to Fig. 30 are explanation diagrams each illustrating details of constituent
components of the electrode unit 50. Fig. 7 and Fig. 8 are explanation diagrams each
schematically illustrating a structure of the chassis 1. Fig. 7 illustrates a planar
structure of the chassis 1, and Fig. 8 illustrates a cross-section structure of the
chassis 1.
[0027] Fig. 9 and Fig. 10 are explanation diagrams each schematically illustrating a structure
of a high voltage side dielectric film 2. Fig. 9 illustrates a planar structure of
the high voltage side dielectric film 2, and Fig. 10 illustrates a cross-section structure
of the high voltage side dielectric film 2.
[0028] Fig. 11 and Fig. 12 are explanation diagrams each schematically illustrating a structure
of a ground side dielectric film 3. Fig. 11 illustrates a planar structure of the
ground side dielectric film 3, and Fig. 12 illustrates a cross-section structure of
the ground side dielectric film 3.
[0029] Fig. 13 and Fig. 14 are explanation diagrams each schematically illustrating a structure
of a power supply body 5. Fig. 13 illustrates a planar structure of the power supply
body 5, and Fig. 14 illustrates a cross-section structure of the power supply body
5.
[0030] Fig. 15 and Fig. 17 are explanation diagrams each schematically illustrating a structure
of a ground conductor 6. Fig. 15 illustrates a planar structure of the ground conductor
6, Fig. 16 illustrates a cross-section structure of the ground conductor 6, and Fig.
17 illustrates details of a focus region R1 in Fig. 16.
[0031] Fig. 18 and Fig. 19 are explanation diagrams each schematically illustrating a structure
of a cover dielectric film 8. Fig. 18 illustrates a planar structure of the cover
dielectric film 8, and Fig. 19 illustrates a cross-section structure of the cover
dielectric film 8.
[0032] Fig. 20 and Fig. 21 are explanation diagrams each schematically illustrating a structure
of a ground side electrode constituting part E2. Fig. 20 illustrates a planar structure
of the ground side electrode constituting part E2, and Fig. 21 illustrates a cross-section
structure of the ground side electrode constituting part E2. The ground side electrode
constituting part E2 includes a combination structure of the ground side dielectric
film 3, a conductive film 7, and the cover dielectric film 8.
[0033] Fig. 22 and Fig. 23 are explanation diagrams each schematically illustrating a structure
of a shield dielectric film 9. Fig. 22 illustrates a planar structure of the shield
dielectric film 9, and Fig. 23 illustrates a cross-section structure of the shield
dielectric film 9.
[0034] Fig. 24 and Fig. 25 are explanation diagrams each schematically illustrating a structure
of a dielectric film support member 10. Fig. 24 illustrates a planar structure of
the dielectric film support member 10, and Fig. 25 illustrates a cross-section structure
of the dielectric film support member 10.
[0035] Fig. 26 to Fig. 28 are explanation diagrams each schematically illustrating a structure
of a dielectric film suppression member 11. Fig. 26 illustrates a planar structure
of the dielectric film suppression member 11, Fig. 27 illustrates a cross-section
structure of the dielectric film suppression member 11, and Fig. 28 illustrates details
of a focus region R2 in Fig. 27.
[0036] Fig. 29 and Fig. 30 are explanation diagrams each schematically illustrating a structure
of a press member 12. Fig. 29 illustrates a planar structure of the press member 12,
and Fig. 30 illustrates a cross-section structure of the press member 12.
[0037] Each of Fig. 1 to Fig. 30 schematically illustrates constituent components of the
active gas generation apparatus 71, the electrode unit 50, or the electrode unit 50,
and a shape including scale reduction does not necessarily coincide with each other
in Fig. 1 to Fig. 30. An XYZ rectangular coordinate system is illustrated in each
of Fig. 1 to Fig. 30.
[0038] The active gas generation apparatus 71 according to the embodiment 1 is described
hereinafter appropriately with reference to Fig. 1 to Fig. 30 described above.
(Whole structure)
[0039] As illustrated in Fig. 1, the active gas generation apparatus 71 includes the electrode
units 51 to 53 as the plurality of electrode units and the chassis 1 housing the electrode
units 51 to 53 in a chassis space S 1 (refer to Fig. 8) and having conductivity.
[0040] As illustrated in Fig. 2 and Fig. 7, the chassis 1 includes a chassis bottom part
1a including a flat surface 1F and a conductor housing space 6S concaved from the
flat surface 1F in a depth direction.
[0041] As illustrated in Fig. 8, the chassis 1 includes the chassis bottom part 1a, a chassis
side part 1b, and a chassis upper part 1c, and the chassis space S1 housing the electrode
units 51 to 53 therein is formed by the chassis bottom part 1a, the chassis side part
1b, and the chassis upper part 1c.
[0042] Each of the electrode units 51 to 53 is housed in the chassis space S 1 in the chassis
1 in a state where the ground conductor 6 is disposed in the conductor housing space
6S. As illustrated in Fig. 7, the material gas G1 supplied from an outer portion is
supplied to a material gas flow space provided in a lower surface and a side surface
of the ground conductor 6 disposed in the conductor housing space 6S through the gas
flow path 21 provided in the chassis bottom part 1a.
[0043] The electrode unit 51 (50) includes a high voltage side electrode constituting part
E1 as a first electrode constituting part and the ground side electrode constituting
part E2 as a second electrode constituting part provided on a lower side of the high
voltage side electrode constituting part E1 as the first electrode constituting part.
[0044] The electrode unit 51 further includes the ground conductor 6 as a reference potential
conductor provided on a lower side of the ground side electrode constituting part
E2 as the second electrode constituting part and housed in the conductor housing space
6S. The ground conductor 6 includes a conductor such as metal as a constituent material.
[0045] The high voltage side electrode constituting part E1 includes the high voltage side
dielectric film 2 as the first electrode dielectric film and the power supply body
5 as the first electrode conductive film formed on the upper surface of the high voltage
side dielectric film 2. The power supply body 5 as the first electrode conductive
film is provided on a power supply body arrangement concave part 28 provided in a
center of the high voltage side dielectric film 2 as the first electrode dielectric
film.
[0046] The high voltage side dielectric film 2 includes a dielectric as a constituent material,
and the power supply body 5 includes a conductor such as metal as a constituent material.
For example, the power supply body 5 is made of metal.
[0047] The ground side electrode constituting part E2 includes the ground side dielectric
film 3 as the second electrode dielectric film and the conductive film 7 as the second
electrode conductive film formed on the lower surface of the ground side dielectric
film 3. The conductive film 7 has a small film thickness, thus illustration thereof
is omitted in Fig. 2 etc., and a formation region of the conductive film 7 is illustrated
in Fig. 20 and Fig. 21.
[0048] The ground side dielectric film 3 includes a dielectric as a constituent material,
and the conductive film 7 includes a conductor such as metal as a constituent material.
[0049] The ground conductor 6 as the reference potential conductor includes an active gas
buffer space 9S which does not pass through an upper portion, and the ground side
electrode constituting part E2 is disposed to cover the active gas buffer space 9S.
Accordingly, a lower surface of the conductive film 7 and an upper surface of the
ground conductor 6 have a contact relationship on an outer side of the active gas
buffer space 9S.
[0050] The ground side dielectric film 3 as the second electrode dielectric film includes
a dielectric through port 3h passing through the ground side dielectric film 3 in
a region overlapped with the active gas buffer space 9S in a plan view, the conductive
film 7 as the second electrode conductive film includes a conductive film opening
part 7h in a region overlapped with the active gas buffer space 9S in a plan view,
and the conductive film opening part 7h is overlapped with the dielectric through
port 3h in a plan view.
[0051] The chassis bottom part 1a of the chassis 1 includes the gas flow path 21 receiving
the material gas G1 from an outer portion, and a material gas flow space is provided
between the ground conductor 6 and the conductor housing space 6S in the chassis 1.
As described hereinafter, the material gas flow space includes a material gas buffer
space 61, a slit space 62, and a side surface space 63.
[0052] The material gas G1 is introduced into a main discharge space of the discharge space
4 through the gas flow path 21 and the material gas flow space described above. As
described hereinafter, the main discharge space indicates the discharge space 4 in
a dielectric space 18 between the high voltage side dielectric film 2 and the ground
side dielectric film 3.
[0053] Alternating-current voltage applied from an alternating-current power source 15 is
applied to the power supply body 5 as the first electrode conductive film via an electrical
connection means such as an electrical wiring or an introduction terminal. Illustration
of the electrical connection means is omitted in Fig. 2 etc.
[0054] In the meanwhile, the chassis 1 is set to have ground potential as reference potential.
Accordingly, the conductive film 7 as the second electrode conductive film is set
to have ground potential via the chassis 1 and the ground conductor 6.
[0055] The electrode unit 51 (50) further includes an auxiliary member such as the dielectric
film support member 10, the dielectric film suppression member 11, and the press member
12.
(Fixation of high voltage side dielectric film 2)
[0056] A level difference part 102 of the dielectric film support member 10 includes an
upper surface serving as a support surface 10F provided on the flat surface 1F of
the chassis 1 to support the high voltage side dielectric film 2 from a lower side.
At this time, the dielectric film support member 10 is disposed on the flat surface
1F so that a side surface of the dielectric film support member 10 and a side surface
of the conductor housing space 6S on the chassis bottom part 1a of the chassis 1 coincide
with each other.
[0057] The dielectric film suppression member 11 is a member for suppressing the high voltage
side dielectric film 2 from an upper side, and is not overlapped with the power supply
body 5 in a plan view. That is to say, an exposed region EX2 where the dielectric
film suppression member 11 and the power supply body 5 are not formed is located on
the upper surface of the high voltage side dielectric film 2.
[0058] As illustrated in Fig. 6, Fig. 27, and Fig. 28, a lower surface of the dielectric
film suppression member 11 includes a dielectric contact region 112 having contact
with the upper surface of the high voltage side dielectric film 2 and a dielectric
non-contact region 111 which does not have contact with the upper surface of the high
voltage side dielectric film 2. The dielectric contact region 112 serves as a region
having contact with the high voltage side dielectric film 2 to apply load, and the
dielectric non-contact region 111 serves as a region protruding to a side of the power
supply body 5 on the upper surface of the high voltage side dielectric film 2 without
having a contact relationship with the high voltage side dielectric film 2.
[0059] The dielectric contact region 112 is overlapped with a peripheral region of the high
voltage side dielectric film 2 and the support surface 10F of the dielectric film
support member 10 in a plan view, and the dielectric non-contact region 111 is overlapped
with an intermediate region on an inner side of the peripheral region of the high
voltage side dielectric film 2. That is to say, the intermediate region is a region
adjacent to a side of the power supply body 5 from the peripheral region of the high
voltage side dielectric film 2.
[0060] The dielectric film suppression member 11 is made of metal etc., has conductivity,
and is set to have ground potential as reference potential via the chassis 1, an attachment
bolt 31, and the press member 12. The attachment bolt 31 and the press member 12 also
have conductivity.
[0061] Accordingly, the high voltage side dielectric film 2 is suppressed by the dielectric
film suppression member 11 from the upper side in the dielectric contact region 112.
A combination structure of the dielectric film support member 10, the dielectric film
suppression member 11, and the press member 12 is described in detail hereinafter.
[0062] As illustrated in Fig. 2, the press member 12 is disposed on the upper surface of
the dielectric film support member 10, and the press member 12 and the dielectric
film support member 10 are fixed on the chassis bottom part 1a of the chassis 1 by
the attachment bolt 31.
[0063] As illustrated in Fig. 24 and Fig. 25, the dielectric film support member 10 has
a circular shape having a center opening part 100 in a center thereof in a plan view.
A level difference structure made up of a level difference part 102 and a peripheral
part upper surface 101 is provided to have an annular shape around the center opening
part 100. An upper surface of the level difference part 102 serves as the support
surface 10F. A plurality of through ports 10h are dispersedly disposed to have a circular
shape in the peripheral part upper surface 101 on a side of an outer periphery of
the level difference part 102 (the support surface 10F).
[0064] In the meanwhile, as illustrated in Fig. 9 and Fig. 10, the high voltage side dielectric
film 2 has a circular shape with the power supply body arrangement concave part 28
in a center thereof in a plan view. A peripheral surface region 27 is provided to
have an annular shape around the power supply body arrangement concave part 28. The
high voltage side dielectric film 2 includes a circular concave part bottom surface
26 in a plan view, and a bottom surface around the concave part bottom surface 26
serves as an annular convex part bottom surface 23.
[0065] As illustrated in Fig. 13 and Fig. 14, the power supply body 5 has a columnar shape.
The power supply body 5 is disposed on the upper surface of the high voltage side
dielectric film 2 while a bottom surface of the power supply body 5 is located on
the power supply body arrangement concave part 28 of the high voltage side dielectric
film 2.
[0066] Alternating-current voltage is applied to the power supply body 5 as the first electrode
conductive film from the alternating-current power source 15. As illustrated in Fig.
5, the power supply body arrangement concave part 28 includes the power supply body
5 in a plan view, and has a planar shape slightly larger than the power supply body
5.
[0067] The high voltage side dielectric film 2 is disposed on the dielectric film support
member 10 while the support surface 10F of the dielectric film support member 10 and
the convex part bottom surface 23 of the high voltage side dielectric film 2 have
contact with each other. The high voltage side dielectric film 2 and the dielectric
film support member 10 have contact with each other via a seal member such as an O
ring not shown in the diagrams.
[0068] As illustrated in Fig. 26 and Fig. 27, the dielectric film suppression member 11
has a circular shape having a center opening part 110 in a center thereof in a plan
view. An annular lower surface region provided on a side of an outer periphery of
the center opening part 110 serves as the dielectric non-contact region 111, and an
annular lower surface region provided on a side of an outer periphery of the dielectric
non-contact region 111 serves as the dielectric contact region 112.
[0069] As illustrated in Fig. 28, the dielectric contact region 112 protrudes to a lower
side of the dielectric non-contact region 111 (-Z direction), and has a contact relationship
with an upper surface U2 of the high voltage side dielectric film 2. In the meanwhile,
a gap SP11 is located between the dielectric non-contact region 111 and the upper
surface U2 of the high voltage side dielectric film 2, thus the dielectric non-contact
region 111 does not have contact with the upper surface U2 of the high voltage side
dielectric film 2.
[0070] As illustrated in Fig. 29 and Fig. 30, the press member 12 has a circular shape having
a center opening part 120 in a center thereof in a plan view. A plurality of inner
through ports 121h are dispersedly disposed to have a circular shape in an outer peripheral
region 125 on a side of an outer periphery of the center opening part 120, and a plurality
of outer through ports 122h are dispersedly disposed to have a circular shape on a
side of an outer periphery of the plurality of inner through ports 121h.
[0071] In this manner, the plurality of inner through ports 121h and the plurality of outer
through ports 122h are provided in the outer peripheral region 125 of the press member
12. Each of the plurality of inner through ports 121h is a through port made by cutting
a tap.
[0072] A part of the outer peripheral region 125 in the press member 12 having the above
structure is disposed on the dielectric film support member 10, and the dielectric
film support member 10 and the press member 12 are fixed to the chassis bottom part
1a of the chassis 1 by the plurality of attachment bolts 31. A screw part of each
of the plurality of attachment bolts 31 passes through the plurality of outer through
ports 122h and the plurality of through ports 10h, and is attached to the chassis
bottom part 1a.
[0073] As illustrated in Fig. 2 to Fig. 6, the press member 12 is disposed in a region overlapped
with the dielectric film support member 10 and the dielectric film suppression member
11 in a plan view.
[0074] In the meanwhile, a plurality of suppression auxiliary members 32 are attached to
the press member 12 while passing through the plurality of inner through ports 121h
of the press member 12. A bolt or a locking screw is considered as the suppression
auxiliary member 32. The plurality of suppression auxiliary members 32 attach the
dielectric film suppression member 11 to an inner side of the plurality of inner through
ports 121h while pressing the dielectric film suppression member 11. The plurality
of suppression auxiliary members 32 are provided in positions overlapped with the
dielectric contact region 112 of the dielectric film suppression member 11 and the
convex part bottom surface 23 of the high voltage side dielectric film 2 in a plan
view.
[0075] Accordingly, the high voltage side dielectric film 2 is suppressed from the dielectric
contact region 112 on an outer side by the dielectric film suppression member 11 receiving
suppress strength of the plurality of suppression auxiliary members 32.
[0076] As described above, in the electrode unit 50 of the active gas generation apparatus
71 according to the embodiment 1, the high voltage side dielectric film 2 as the first
electrode dielectric film is suppressed from the dielectric contact region 112 on
the upper side by the dielectric film suppression member 11 receiving suppress strength
of the plurality of suppression auxiliary members 32. Thus, a region in which load
is applied to the high voltage side dielectric film 2 by the dielectric film suppression
member 11 can be limited to a lower region of the dielectric contact region 112.
[0077] As a result, the active gas generation apparatus 71 according to the embodiment 1
can stably fix the high voltage side dielectric film 2 between the dielectric contact
region 112 of the dielectric film suppression member 11 and the support surface 10F
of the dielectric film support member 10 without unnecessary bending stress applied
to the high voltage side dielectric film 2.
[0078] The dielectric film suppression member 11 is set to have ground potential as reference
potential, and has conductivity. The dielectric non-contact region 111 of the dielectric
film suppression member 11 is overlapped with the intermediate region of the high
voltage side dielectric film 2 in a plan view.
[0079] Accordingly, the electrode unit 50 can reduce electrical field strength of the power
supply body 5 by the dielectric film suppression member 11 including the dielectric
non-contact region 111 to reduce potential of the intermediate region of the high
voltage side dielectric film 2, thus potential of the high voltage side dielectric
film 2 and the ground side dielectric film 3 in an outer diameter direction can be
reduced.
[0080] As a result, the electrode unit 50 in the active gas generation apparatus 71 according
to the embodiment 1 can reliably prevent insulation breakdown in a gap 20 between
the high voltage side dielectric film 2 and the dielectric film support member 10.
(Ground conductor 6)
[0081] As illustrated in Fig. 15 to Fig. 17, the ground conductor 6 housed in the conductor
housing space 6S in the chassis 1 has a circular shape in a plan view, and includes
the material gas buffer space 61 and the slit space 62 in an end portion region in
the bottom surface.
[0082] The material gas buffer space 61 is formed into an annular shape in a plan view,
and is connected to the gas flow path 21 as illustrated in Fig. 2, thus can take the
material gas G1 supplied from an outer portion in the material gas buffer space 61
via the gas flow path 21.
[0083] The plurality of slit spaces 62 are dispersedly provided around the material gas
buffer space 61. As illustrated in Fig. 17, each of the plurality of slit spaces 62
is connected to the material gas buffer space 61, and the material gas G1 can flow
from the material gas buffer space 61 to the slit space 62.
[0084] As illustrated in Fig. 6 and Fig. 17, the side surface space 63 is a gap space between
an inner peripheral side surface of the conductor housing space 6S and an outer peripheral
side surface of the ground conductor 6, and is annularly provided in a plan view.
[0085] The dielectric film support member 10 and the ground conductor 6 have a positional
relationship as illustrated in Fig. 3 and Fig. 4, thus the material gas G1 passing
through the side surface space 63 is supplied to a lower side surface region R10 in
the dielectric film support member 10.
[0086] In this manner, the material gas buffer space 61 is provided on the side of the lower
surface of the ground conductor 6 to receive the material gas G1 through the gas flow
path 21. Each of the plurality of slit spaces 62 is provided on the side of the lower
surface of the ground conductor 6, and is connected to the material gas buffer space
61.
[0087] The side surface space 63 is provided on a side of the side surface of the ground
conductor 6, and is connected to the plurality of slit spaces. As described above,
the material gas flow space includes the material gas buffer space 61, the plurality
of slit spaces 62, and the side surface space 63.
[0088] Accordingly, the material gas G1 supplied to the gas flow path 21 from the outer
portion is introduced into the discharge space 4 through the material gas buffer space
61, the slit space 62, and the side surface space 63.
[0089] Each of the plurality of slit spaces 62 is set to be a narrow space in which material
gas hardly flows compared with the material gas buffer space 61 so that the material
gas G1 temporarily remains in the material gas buffer space 61, and then flows into
each of the plurality of slit spaces 62. That is to say, the plurality of slit spaces
62 are set to have small conductance as a coefficient expressing a degree of flowability
of the material gas G1 compared with the material gas buffer space 61 and the side
surface space 63.
[0090] As a result, the active gas generation apparatus 71 according to the embodiment 1
can uniformly supply the material gas G1 spatially to the discharge space 4. That
is to say, the material gas G1 is uniformly supplied from a peripheral part of the
circular dielectric space 18 toward the discharge space 4 in the center in a plan
view.
[0091] The conductance of the slit space 62 is set to be small, thus differential pressure
between the material gas buffer space 61 and the side surface space 63 increases,
and fluctuation of a flow amount of the material gas G1 flowing in each of the plurality
of slit spaces 62 is reduced. Accordingly, the material gas G1 is uniformly supplied
toward the discharge space 4. A flow amount of the material gas G1 is adjusted by
a mass flow controller (MFC) provided on an upstream of the gas flow path 21, for
example.
[0092] Accordingly, when the material gas G1 is not uniformly supplied in a general active
gas generation apparatus, a time of the material gas G1 passing through the discharge
space 4 is changed, and as a result, a failure of deterioration of generation efficiency
of the active gas G2 occurs. The active gas generation apparatus 71 according to the
embodiment 1 can uniformly supply the material gas G1, thus the failure described
above does not occur.
(Ground side electrode constituting part E2 and active gas buffer space 9S)
[0093] As described above, the ground side electrode constituting part E2 as the second
electrode constituting part includes the ground side dielectric film 3 and the conductive
film 7.
[0094] As illustrated in Fig. 11 and Fig. 12, the ground side dielectric film 3 has a circular
shape in a plan view, and includes the circular dielectric through port 3h in the
center thereof.
[0095] As illustrated in Fig. 18 and Fig. 19, the cover dielectric film 8 has a circular
shape in a plan view, and includes a circular cover through port 8h in the center
thereof. It is preferable that the same constituent material is used for the cover
dielectric film 8 and the ground side dielectric film 3. The reason is that occurrence
of distortion is prevented in a case where a thermal expansion coefficient is different
between the cover dielectric film 8 and the ground side dielectric film 3. It is also
applicable to select a material having a close thermal expansion coefficient as a
material of each of the cover dielectric film 8 and the ground side dielectric film
3.
[0096] As illustrated in Fig. 20 and Fig. 21, the conductive film 7 has a circular shape
in a plan view, and includes the circular conductive film opening part 7 in the center
thereof in a plan view.
[0097] Each of the dielectric through port 3h and the conductive film opening part 7h is
overlapped with an active gas buffer space 68 in a plan view, and as illustrated in
Fig. 21, the conductive film opening part 7h includes the dielectric through port
3h and has a shape larger than the dielectric through port 3h in a plan view.
[0098] The conductive film 7 is provided on the lower surface of the ground side dielectric
film 3 while a center position of each of the ground side dielectric film 3 and the
conductive film 7 coincides with each other. A diameter of the conductive film 7 is
set to be substantially the same as that of the ground side dielectric film 3, however,
a formation area of the conductive film 7 is smaller than that of the ground side
dielectric film 3 by reason that the conductive film opening part 7h larger than the
dielectric through port 3h is provided in the center thereof.
[0099] A conductive film inner boundary 7e as a circumferential outer peripheral line of
the conductive film opening part 7h serves as an end portion of the conductive film
7 on a side of the dielectric through port 3h, and the conductive film 7 is not formed
in a region on an inner side of the conductive film inner boundary 7e. The conductive
film inner boundary 7e serves as an electrode boundary line of the conductive film
7. Accordingly, as illustrated in Fig. 21, a formation region A7 of the conductive
film 7 on the lower surface of the ground side dielectric film 3 is a region ranging
from a position of an outer periphery of the ground side dielectric film 3 to the
conductive film inner boundary 7e.
[0100] As illustrated in Fig. 20 and Fig. 21, the cover dielectric film 8 is provided to
have a circular shape from the lower surface of the ground side dielectric film 3
to the lower surface of the conductive film 7 while including the conductive film
inner boundary 7e. However, the cover dielectric film 8 includes the cover through
port 8h in a center thereof. That is to say, there is a dimensional relationship that
an outer diameter of the conductive film opening part 7h of the conductive film 7
is smaller than that of the cover dielectric film 8.
[0101] The cover through port 8h has substantially the same shape as the dielectric through
port 3h, and is included in the conductive film opening part 7h, thus has a shape
smaller than the conductive film opening part 7h. Accordingly, the cover dielectric
film 8 covers the conductive film inner boundary 7e (electrode boundary line) of the
conductive film 7. The lower surface of the conductive film 7 which is not covered
by the cover dielectric film 8 and the upper surface of the ground conductor 6 have
a contact relationship with each other.
[0102] As illustrated in Fig. 15 and Fig. 16, the active gas buffer space 68 provided on
the upper portion of the ground conductor 6 has a circular shape in a plan view, and
a plurality of gas ejection ports 69 are provided around a bottom surface 65 of the
active gas buffer space 68.
[0103] Fig. 15 and Fig. 16 also illustrate a formation region of the cover dielectric film
8. As illustrated in Fig. 15 and Fig. 16, an outer peripheral line of the cover dielectric
film 8 is substantially the same as that of the active gas buffer space 68.
[0104] As illustrated in Fig. 2 and Fig. 16, the shield dielectric film 9 is provided on
the bottom surface 65 of the active gas buffer space 68.
[0105] As illustrated in Fig. 22 and Fig. 23, the shield dielectric film 9 is formed into
a circular shape with a predetermined film thickness in a plan view.
[0106] The shield dielectric film 9 is provided on the bottom surface 65 of the active gas
buffer space 68 while a center position of each of the active gas buffer space 68
and the shield dielectric film 9 coincides with each other.
[0107] As illustrated in Fig. 15 and Fig. 16, the plurality of gas ejection ports 69 are
overlapped with the cover dielectric film 8 in a plan view, and are not overlapped
with the dielectric through port 3h and the cover through port 8h in a plan view.
[0108] As illustrated in Fig. 16, the plurality of gas ejection ports 69 are provided around
the bottom surface 65 of the active gas buffer space 68 to pass through the ground
conductor 6. That is to say, the plurality of gas ejection ports 69 are provided in
a peripheral region of the shield dielectric film 9 in a plan view.
[0109] In the active gas generation apparatus 71 according to the embodiment 1 having such
a structure, the material gas G1 is supplied from the outer portion of the metal chassis
2 to the discharge space 4 through the gas flow path 21 and the material gas flow
space as described above.
[0110] When the material gas G1 is supplied to the discharge space 4 where the dielectric
barrier discharge occurs, the material gas G1 is activated to be the active gas G2,
and passes through the dielectric through port 3h and the cover through port 8h to
be introduced into the active gas buffer space 68. The active gas G2 entering the
active gas buffer space 68 passes through the plurality of gas ejection ports 69 provided
in the bottom surface of the active gas buffer space 68 to be supplied to a processing
space in a subsequent stage.
[0111] In the active gas generation apparatus 71 according to the embodiment 1 having such
a configuration, a main dielectric space where the high voltage side dielectric film
2 as the first electrode dielectric film and the ground side dielectric film 3 as
the second electrode dielectric film face each other serves as the dielectric space
18. The dielectric space 18 has a circular shape in a plan view. A space where the
high voltage side dielectric film 2 and the shield dielectric film 9 face each other
is defined as an auxiliary dielectric space. The discharge space 4 includes a main
discharge space where the power supply body 5 and the conductive film 7 are overlapped
with each other in a plan view in the dielectric space 18.
[0112] The high voltage side dielectric film 2 and the ground side dielectric film 3 are
disposed to correspond to each other so as to have a constant distance therebetween
in a height direction (Z direction), and the main discharge space described above
is located in the dielectric space 18 between the high voltage side dielectric film
2 and the ground side dielectric film 3.
[0113] The discharge space 4 further includes an auxiliary discharge space 44 made up of
the dielectric through port 3h, the cover through port 8h, and a part of the active
gas buffer space 68 on the shield dielectric film 9 in the auxiliary dielectric space
described above.
[0114] A bottom surface region below the bottom surface 65 of the ground conductor 6 is
used as a ground electrode conductive film set to have ground potential, and discharge
voltage is applied between the power supply body 5 receiving alternating current voltage
from the alternating-current power source 15 and the ground electrode conductive film
described above, thus the auxiliary discharge space 44 can be generated.
[0115] As described above, the auxiliary discharge space 44 includes the dielectric through
port 3h, the cover through port 8h, and a part of the active gas buffer space 68.
In this manner, the discharge space 4 formed in the embodiment 1 includes the main
discharge space and the auxiliary discharge space 44 in the dielectric space 18.
[0116] In the active gas generation apparatus 51 according to the embodiment 1, a path from
the auxiliary discharge space 44 to each of the plurality of gas ejection ports 69
is defined as the active gas flow path.
[0117] In the active gas generation apparatus 71 according to the embodiment 1, the auxiliary
discharge space 44 as a part of the discharge space 4 includes the dielectric through
port 3h, the cover through port 8h, and a part of the active gas buffer space 68,
thus can suppress the active gas flow path from the auxiliary discharge space 44 to
the plurality of gas ejection ports 69 to have a minimum necessary volume to suppress
a deactivation amount of the active gas G2.
[0118] Furthermore, the cover dielectric film 8 in the ground side electrode constituting
part E2 of the electrode unit 50 covers the conductive film inner boundary 7e as the
electrode boundary line of the conductive film 7 in the active gas buffer space 68,
and is overlapped with the plurality of gas ejection ports 69 in a plan view, thus
can suppress a surface deactivation phenomenon in which the active gas G2 gets dissipated
due to collision of the active gas G2 with the conductive film 7.
[0119] As a result, the active gas generation apparatus 71 according to the embodiment 1
can supply the high concentration active gas G2 from the plurality of gas ejection
ports 69 to the processing space in the subsequent stage.
[0120] The electrode unit 50 according to the embodiment 1 has the structure described above,
thus only the components (the high voltage side dielectric film 2, the ground side
dielectric film 3, the cover dielectric film 8, and the shield dielectric film 9)
made up of the dielectric serving as the insulator as the constituent material face
the discharge space 4. When a metal material faces discharge, it is easily ionized,
and metal ions is included in gas, thus causes contamination. In the meanwhile, even
when the dielectric faces discharge, it is not easily ionized, thus can prevent contamination
in the gas.
(Chassis opening part 41)
[0121] As illustrated in Fig. 2, the chassis bottom part 1a of the chassis 1 includes a
chassis opening part 41. The chassis opening part 41 is provided in a region overlapped
with the active gas buffer space 68 in a plan view, and passes through the chassis
bottom part 1a.
[0122] Accordingly, the active gas G2 ejected from the plurality of gas ejection ports 69
is introduced into the processing space on the lower side through the chassis opening
part 41.
[0123] As illustrated in Fig. 2, the chassis opening part 41 provided in the chassis bottom
part 1a has a larger opening area with decreasing distance to the lower side, and
has a tapered shape with a lowermost outer peripheral edge 41L as illustrated in Fig.
2 and Fig. 7.
[0124] In the active gas generation apparatus 71 according to the embodiment 1, the chassis
opening part 41 provided in the chassis bottom part 1a of the chassis 1 has the tapered
shape with the larger opening area with decreasing distance to the lower side.
[0125] Accordingly, the active gas generation apparatus 71 according to the embodiment 1
can suppress loss of the active gas G2 ejected from the plurality of gas ejection
ports 69 due to collision of the active gas G2 with the chassis bottom part 1a to
a minimum, thus can supply the high concentration active gas G2 to the processing
space on the lower side.
<Embodiment 2>
[0126] Fig. 31 is a plan view schematically illustrating a planar structure of an active
gas generation apparatus 72 as an embodiment 2 according to the present disclosure.
Fig. 32 is a cross-sectional view illustrating a cross-section structure of a D-D
cross section in Fig. 31.
[0127] The same sign is assigned to the same constituent parts as those in the active gas
generation apparatus 71 according to the embodiment 1 illustrated in Fig. 1 to Fig.
30, and characterizing portions of the active gas generation apparatus 72 according
to the embodiment 2 is mainly described hereinafter.
[0128] In the active gas generation apparatus 72 according to the embodiment 2, three electrode
units 51 to 53 as the plurality of electrode units are housed in the chassis space
S1 in a chassis 1X. Material gas G1 is supplied to each of the electrode units 51
to 53 through the gas flow path 21.
[0129] A cooling path in which a cooling medium flows is further provided in addition to
the gas flow path 21 in the chassis bottom part 1a of the chassis 1X in the active
gas generation apparatus 72. As illustrated in Fig. 31 and Fig. 32, the cooling path
22 is provided on the lower side of the ground conductor 6 of each of the electrode
units 51 to 53. That is to say, the cooling path 22 and the ground conductor 6 of
each of the electrode units 51 to 53 are overlapped with each other in a plan view.
[0130] The active gas generation apparatus 72 according to the embodiment 2 having the configuration
describe above has an effect described hereinafter in addition to the effect in the
embodiment 1.
[0131] In the active gas generation apparatus 72 according to the embodiment 2, the chassis
bottom part 1a of the chassis 1X includes the cooling path 22 in which the cooling
medium flows, thus the ground conductor 6 of each of the electrode units 51 to 53
and the ground side dielectric film 3 disposed on the upper side of the ground conductor
6 can be cooled.
[0132] Accordingly, heat generated by dielectric barrier discharge in the discharge space
4 can be removed by the ground side dielectric film 3 which has been cooled. As a
result, the active gas generation apparatus 72 according to the embodiment 2 can perform
discharge at high power in each of the electrode units 51 to 53, thus can achieve
a high concentration of the active gas G2.
<Embodiment 3>
[0133] Fig. 33 and Fig. 34 are explanation diagrams each illustrating a structure of a power
supply body 5B used in each of the electrode units 51 to 53 in an active gas generation
apparatus 73 according to an embodiment 3. Fig. 33 illustrates a planar structure
of the power supply body 5B, and Fig. 34 illustrates a cross-section structure of
an E-E cross section in Fig. 33.
[0134] The active gas generation apparatus 73 according to the embodiment 3 has a feature
that the power supply body 5 is replaced with the power supply body 5B in comparison
with the embodiment 1. Accordingly, a whole structure of the active gas generation
apparatus 73 and a whole structure of the electrode unit 50 (5G10) are similar to
the structure according to the embodiment 1 illustrated in Fig. 1 to Fig. 30 or the
embodiment 2 illustrated in Fig. 31 and Fig. 32.
[0135] At this time, a lower surface of the power supply body 5B in the electrode unit 50
and the upper surface of the high voltage side dielectric film 2 have a contact relationship
with each other via a solution having conductivity. "Galinstan" (registered trademark)
is considered as such a solution, for example.
[0136] The same sign is assigned to the same constituent parts as those in the active gas
generation apparatus 71 according to the embodiment 1, and characterizing portions
of the active gas generation apparatus 73 according to the embodiment 3 is mainly
described hereinafter.
[0137] The power supply body 5B as the first electrode conductive film includes a cooling
medium flow path 58 flowing a cooling medium into an inner portion of the power supply
body 5B. As illustrated in Fig. 33 and Fig. 34, the cooling medium flow path 58 is
provided in a major part of a region of the power supply body 5B while meandering
in a plan view to flow the cooling medium into the whole power supply body 5B.
[0138] The power supply body 5B includes, in a surface thereof, a cooling medium inlet 56
for receiving the cooling medium from the outer portion and supply the cooling medium
to the cooling medium flow path 58 and a cooling medium outlet 57 for exhausting the
cooling medium flowing in the cooling medium flow path 58 to the outer portion.
[0139] Fig. 35 is an explanation diagram schematically illustrating a cooling structure
in a basic configuration according to the embodiment 3. As illustrated in Fig. 35,
the cooling medium is supplied from the outer portion along a flow D1, and is exhausted
to the outer portion along a flow D2 of the cooling medium. As illustrated in Fig.
35, a cooling function is achieved by current introduction members 14A and 14B and
the power supply body 5B.
[0140] In the basic configuration of the embodiment 3, the cooling structure illustrated
in Fig. 35 is provided in each of the electrode units 51 to 53 as the plurality of
electrode units.
[0141] As illustrated in Fig. 35, the current introduction members 14A and 14B are provided
to pass through the chassis upper part 1c of the chassis 1 (1X). The current introduction
members 14A and 14B serving as first and second current introduction members have
the same structure. The current introduction member 14A in the current introduction
members 14A and 14B is representatively described hereinafter.
[0142] The current introduction member 14A includes a conduction pipe 141, a flange 142,
and an insulator 143 as main constituent elements. The conduction pipe 141 and the
flange 142 have conductivity, and the insulator 143 has an insulation property.
[0143] The conduction pipe 141 is used as an electrical connection means of electrically
connecting the alternating-current power source 15 and the power supply body 5B, and
further includes a through port through which the cooling medium can be transported.
[0144] In the current introduction member 14A, the conduction pipe 141 and the insulator
143 are joined, the flange 142 and the insulator 143 are joined, thus the conduction
pipe 141, the flange 142, and the insulator 143 have an integrated structure. However,
the insulator 143 is provided between the conduction pipe 141 and the flange 142,
thus an electrical connection between the conduction pipe 141 and the flange 142 is
prevented.
[0145] Each of the current introduction members 14A and 14B are fixed to the chassis upper
part 1c of the chassis 1X by the flange 142.
[0146] The current introduction member 14A as the first current introduction member has
an electrical connection relationship with the power supply body 5B, and is connected
to the power supply body 5B so that the cooling medium can be supplied from the cooling
medium inlet 56 to the cooling medium flow path 58 through the conduction pipe 141.
That is to say, the current introduction member 14A is electrically connected to the
power supply body 5B by the conduction pipe 141, and the cooling medium flowing in
the conduction pipe 141 is supplied from the cooling medium inlet 56 to the cooling
medium flow path 58.
[0147] The current introduction member 14B as the second current introduction member has
an electrical connection relationship with the power supply body 5B, and is connected
to the power supply body 5B so that the cooling medium can be exhausted to the outer
portion from the cooling medium outlet 57 through the conduction pipe 141. That is
to say, the current introduction member 14B is electrically connected to the power
supply body 5B by the conduction pipe 141, and the cooling medium flowing in the conduction
pipe 141 is supplied to the outer portion.
[0148] Joining by welding or connection via a j oint, for example, is adopted as a means
of connecting the conduction pipe 141 and the power supply body 5B in each of the
current introduction members 14A and 14B.
[0149] The active gas generation apparatus 73 as the basic configuration according to the
embodiment 3 having the configuration describe above has an effect described hereinafter
in addition to the effect in the embodiment 1.
[0150] In the active gas generation apparatus 73 according to the embodiment 3, the power
supply body 5B includes the cooling medium flow path 58 therein, thus when the cooling
medium supplied from the cooling medium inlet 56 flows into the cooling medium flow
path 58 and is then exhausted to the outer portion from the cooling outlet 57, the
power supply body 5B and the high voltage side dielectric film 2 provided on the lower
side of the power supply body 5B can be cooled.
[0151] The current introduction members 14A and 14B further include the cooling structure
of circulating the cooling medium to the cooling medium flow path 58 of the power
supply body 5B in addition to the current introduction function of providing the alternating-current
voltage from the alternating-current power source 15 to the power supply body 5B,
thus can cool each of the current introduction members 14A and 14B while reducing
the number of components to a minimum necessary.
[0152] Allowable current of the current introduction members 14A and 14B is generally determined
by an allowable temperature of the current introduction members 14A and 14B, thus
the allowable current can be significantly increased even in the current introduction
members 14A and 14B in which the conduction pipe 141 made up of a thin conductor is
used by the configuration capable of cooling the current introduction members 14A
and 14B themselves.
[0153] Furthermore, the solution having conductivity is provided between the high voltage
side dielectric film 2 and the power supply body 5B, thus thermal conductivity between
the power supply body 5B and the high voltage side dielectric film 2 can be increased,
and a problem that a minute gap occurs between the power supply body 5B and the high
voltage side dielectric film 2 due to a tolerance or surface roughness in processing
can be resolved.
[0154] According to the effect described above, each of the electrode units 51 to 53 in
the active gas generation apparatus 71 according to the embodiment 3 can perform discharge
at high power, and a high concentration of the active gas G2 can be achieved.
(Modification example)
[0155] Fig. 36 is an explanation diagram schematically illustrating a cooling structure
in an active gas generation apparatus 73X as a modification example of the embodiment
3.
[0156] Fig. 36 illustrates the electrode units 51 and 52 as the first and second electrode
units. The same sign is assigned to the same constituent parts as those in the active
gas generation apparatus 71 according to the embodiment 1 and the active gas generation
apparatus 73 as the basic configuration of the embodiment 3, and characterizing portions
of the active gas generation apparatus 73X as the modification example of the embodiment
3 is mainly described hereinafter.
[0157] In the description hereinafter, the cooling medium flow path 58, the cooling medium
inlet 56, and the cooling medium outlet 57 of the power supply body 5 in the electrode
unit 51 as the first electrode unit are defined as the first cooling medium flow path,
the first cooling medium inlet, and the first cooling medium outlet, respectively,
for convenience of explanation.
[0158] In the similar manner, the cooling medium flow path 58, the cooling medium inlet
56, and the cooling medium outlet 57 in the electrode unit 52 as the second electrode
unit are defined as the second cooling medium flow path, the second cooling medium
inlet, and the second cooling medium outlet, respectively.
[0159] As illustrated in Fig. 36, a buffer conductor 13 and relay conduction pipes 131 to
134 are added as new constituent elements in the active gas generation apparatus 73X
of the modification example. The buffer conductor 13 serves as a cooling medium relay
member, and the relay conduction pipes 131 to 134 serve as first to fourth relay conduction
pipes.
[0160] The buffer conductor 13 as the cooling medium member has conductivity, and includes
a relay cooling medium flow path 135 provided in an inner portion and through flow
paths 136 and 137 as first and second through flow paths each provided to pass through
a lower surface from an upper surface of the buffer conductor 13.
[0161] The relay conduction pipes 131 to 134 as the first to fourth relay conduction pipes
have conductivity and also have a cooling medium transportation function.
[0162] It is preferable that a part of each of the relay conduction pipes 131 to 134 has
an accordion shape. The part of each of the relay conduction pipes 131 to 134 preferably
has the accordion shape by reason that a deviation of a distance from the buffer conductor
13 to the upper surface of the power supply body 5B caused by a tolerance of components
is absorbed, that is to say, a tolerance in manufacturing the active gas generation
apparatus 73X is absorbed.
[0163] The tolerance described above is obtained by integrating not only a tolerance of
lengths of the relay conduction pipes 131 to 134 but also a tolerance of a height
of the power supply body 5B and a tolerance of a thickness of the high voltage side
dielectric film 2 located on the lower portion of the power supply body 5, for example.
[0164] The relay conduction pipes 131 to 134 as the first to fourth relay conduction pipes
are disposed between the buffer conductor 131 as the cooling medium relay member and
the power supply body 5B of each of the electrode units 51 and 52 to satisfy first
to fourth cooling medium flow conditions described hereinafter.
[0165] The first cooling medium flow condition ··· A condition that the cooling medium flows
between the conduction pipe 141 of the current introduction member 14A and the first
cooling medium inlet through the through flow path 136 and the relay conduction pipe
131.
[0166] The second cooling medium flow condition ··· A condition that the cooling medium
flows between the first cooling medium outlet and the relay cooling medium flow path
135 through the relay conduction pipe 132.
[0167] The third cooling medium flow condition ... A condition that the cooling medium flows
between the relay cooling medium flow path 135 and the second cooling medium inlet
through the relay conduction pipe 133.
[0168] The fourth cooling medium flow condition ... A condition that the cooling medium
flows between the second cooling medium outlet and the conduction pipe 141 of the
current introduction member 14B through the relay conduction pipe 134 and the through
flow path 137.
[0169] In this manner, the current introduction members 14A and 14B are commonly used in
the electrode units 51 and 52 in the active gas generation apparatus 73X as the modification
example.
[0170] The active gas generation apparatus 73X as the modification example of the embodiment
3 having the configuration describe above has an effect described hereinafter in addition
to the effect of the basic configuration in the embodiment 1 and the embodiment 3.
[0171] In the active gas generation apparatus 73X as the modification example of the embodiment
3, the relay conduction pipes 131 to 134 are disposed between the buffer conductor
13 and the power supply body 5B of each of the electrode units 51 and 52 so as to
satisfy the first to fourth cooling medium flow conditions described above. As a result,
the active gas generation apparatus 73X of the modification example can circulate
the cooling medium to one loop of the cooling medium to cool the power supply body
5B of the electrode unit 51 and the power supply body 5B of the electrode 52 together.
[0172] One loop of the cooling medium includes the current introduction member 14A, the
through flow path 136, the relay conduction pipe 131, the first cooling medium inlet,
the first cooling medium flow path, the first cooling medium outlet, the relay conduction
pipe 132, the relay cooling medium flow path 135, the relay conduction pipe 133, the
second cooling medium inlet, the second cooling medium flow path, the second cooling
medium outlet, the relay conduction pipe 134, the through flow path 137, and the current
introduction member 14B.
[0173] As a result, in the active gas generation apparatus 73X of the modification example
of the embodiment 3, the power supply body 5B of each of the electrode units 51 and
52 and the high voltage side dielectric film 2 can be cooled with the minimum necessary
apparatus configuration that the buffer conductor 13 and the relay conduction pipes
131 to 134 are added without increasing the number of relatively expensive current
introduction members 14A and 14B.
[0174] The modification example illustrated in Fig. 36 indicates the cooling structure regarding
the combination of the electrode units 51 and 52. The cooling structure regarding
the combination of the electrode units 51 to 53 can be achieved only by the current
introduction members 14A and 14B by expanding the cooling structure of the modification
example.
<Embodiment 4>
[0175] Fig. 37 is an explanation diagram illustrating a cross-section structure of an electrode
unit 50X used in an active gas generation apparatus 74 according to the embodiment
4. The electrode unit 50X corresponds to any of the electrode units 51 to 53 described
in the embodiment 1. A whole configuration of the active gas generation apparatus
74 is similar to that of the active gas generation apparatus 71 illustrated in Fig.
1.
[0176] Fig. 38 and Fig. 39 are explanation diagrams each schematically illustrating a structure
of a high voltage side dielectric film 2B. Fig. 38 illustrates a planar structure
of the high voltage side dielectric film 2B, and Fig. 39 illustrates a cross-section
structure of the high voltage side dielectric film 2B.
[0177] The electrode unit 50X has a feature that the high voltage side dielectric film 2
of the electrode unit 50 according to the embodiment 1 is replaced with the high voltage
side dielectric film 2.
[0178] The same sign is assigned to the same constituent parts as those in the electrode
unit 50 according to the embodiment 1, and characterizing portions of the electrode
unit 50X according to the embodiment 4 is mainly described hereinafter.
[0179] As illustrated in Fig. 38, the high voltage side dielectric film 2B includes an insulator
structure part 24 having a triple circular structure in a plan view on the peripheral
surface region 27 around the power supply body arrangement concave part 28. The insulator
structure part 24 has a concave-convex structure provided on an upper surface of the
high voltage side dielectric film 2B. Fig. 38 illustrates the insulator structure
part 24 formed of a dielectric made up of the same constituent material as the high
voltage side dielectric film 2B.
[0180] As illustrated in Fig. 37, the high voltage side dielectric film 2B in the electrode
unit 50X includes the insulator structure part 24 having the concave-convex structure
on an upper surface thereof which is not overlapped with the power supply body 5 and
the dielectric film suppression member 11 in a plan view. That is to say, in the embodiment
4, the insulator structure part 24 is provided on the upper surface thereof corresponding
to the exposed region EX2 of the high voltage side dielectric film 2 according to
the embodiment 1 illustrated in Fig. 2, for example. Fig. 37 illustrates the insulator
structure part 24 formed of the dielectric.
[0181] Accordingly, as illustrated in Fig. 37, the electrode unit 50X according to the embodiment
4 includes the insulator structure part 24 between the dielectric film suppression
member 11 and the power supply body 5 on the upper surface of the high voltage side
dielectric film 2B.
[0182] First and second methods described hereinafter are considered as a method of forming
the insulator structure part 24. The first method is a method of performing cutting
process on a flat upper surface of a basic structure of the high voltage side dielectric
film 2B to manufacture the high voltage side dielectric film 2B selectively including
the insulator structure part 24 on the upper surface thereof. In a case of the first
method, the insulator structure part 24 is made up of the same constituent material
as the high voltage side dielectric film 2B.
[0183] The second method is a method of selectively bonding the insulator structure part
24 with an adhesive agent on a flat upper surface of a basic structure of the high
voltage side dielectric film 2B after separately manufacturing the insulator structure
part 24, thereby manufacturing the high voltage side dielectric film 2B. In a case
of the second method, the insulator structure part 24 may be made up of the same constituent
material as the high voltage side dielectric film 2B, or may also be made up of a
different constituent material.
[0184] In the active gas generation apparatus 74 according to the embodiment 4, the high
voltage side dielectric film 2B of the electrode unit 50X includes the insulator structure
part 24 having the concave-convex structure between the dielectric film suppression
member 11 and the power supply body 5 on the upper surface thereof, thus can prevent
creeping discharge between the power supply body 5 and the dielectric film suppression
member 11.
[0185] In the embodiment 4 illustrated in Fig. 37 to Fig. 39, the constituent material of
the insulator structure part 24 is the same dielectric as that of the high voltage
side dielectric film 2B, however, the insulator structure part 24 may also be formed
of a constituent material other than the dielectric different from that of the high
voltage side dielectric film 2B.
[0186] The present disclosure is described in detail, however, the foregoing description
is in all aspects illustrative, thus the present disclosure is not limited thereto.
It is therefore understood that numerous modification examples not exemplified can
be devised without departing from the scope of the present disclosure.
[0187] That is to say, each embodiment can be arbitrarily combined, or each embodiment can
be appropriately varied or omitted within a scope of the present disclosure.
EXPLANATION OF REFERENCE SIGNS
[0188]
1, 1X chassis
2, 2B high voltage side dielectric film
3 ground side dielectric film
4 discharge space
5, 5B power supply body
6 ground conductor
7 conductive film
8 cover dielectric film
9 shield dielectric film
9S active gas buffer space
10 dielectric film support member
11 dielectric film suppression member
12 press member
13 buffer conductor
14A, 14B current introduction member
21 gas flow path
22 cooling path
24 insulator structure part
41 chassis opening part
50, 50X, 51 to 53 electrode unit
56 cooling medium inlet
57 cooling medium outlet
58 cooling medium flow path
61 material gas buffer space
62 slit space
63 side surface space
69 gas ejection port
71 to 74, 73X active gas generation apparatus
131 to 134 relay conduction pipe
E1 high voltage side electrode constituting part
E2 ground side electrode constituting part
1. An active gas generation apparatus activating material gas supplied to a discharge
space to generate active gas, comprising:
an electrode unit; and
a chassis housing the electrode unit in a chassis space and having conductivity, wherein
the chassis includes a chassis bottom part including a flat surface and a conductor
housing space concaved from the flat surface in a depth direction,
the electrode unit includes:
a first electrode constituting part;
a second electrode constituting part provided on a lower side of the first electrode
constituting part; and
a reference potential conductor provided on a lower side of the second electrode constituting
part and housed in the conductor housing space,
the first electrode constituting part includes a first electrode dielectric film and
a first electrode conductive film formed on an upper surface of the first electrode
dielectric film,
the second electrode constituting part includes a second electrode dielectric film
and a second electrode conductive film formed on a lower surface of the second electrode
dielectric film,
the reference potential conductor includes an active gas buffer space on an upper
portion, and the second electrode constituting part is disposed to cover the active
gas buffer space,
the second electrode dielectric film includes a dielectric through port passing through
the second electrode dielectric film in a region overlapped with the active gas buffer
space in a plan view, the second electrode conductive film includes a conductive film
opening part in a region overlapped with the active gas buffer space in a plan view,
and the conductive film opening part is overlapped with the dielectric through port
in a plan view,
the chassis bottom part includes a gas flow path receiving material gas from an outer
portion,
a material gas flow space is provided between the reference potential conductor and
the conductor housing space of the chassis,
a space where the first electrode dielectric film and the second electrode dielectric
film face each other is defined as a main dielectric space,
the discharge space includes a main discharge space as a region in which the first
and second electrode conductive films are overlapped with each other in a plan view
in the main dielectric space,
material gas is introduced into the discharge space via the gas flow path and the
material gas flow space,
alternating-current voltage is applied to the first electrode conductive film, and
the second electrode conductive film is set to have reference potential via the chassis
and the reference potential conductor,
the active gas generation apparatus further includes:
a dielectric film support member provided on the flat surface of the chassis and including
a support surface supporting the first electrode dielectric film from a lower side;
and
a dielectric film suppression member for suppressing the first electrode dielectric
film from an upper side, the dielectric film suppression member not being overlapped
with the first electrode conductive film in a plan view,
a lower surface of the dielectric film suppression member includes a dielectric contact
region having contact with an upper surface of the first electrode dielectric film
and a dielectric non-contact region not having contact with an upper surface of the
first electrode dielectric film, the dielectric contact region is overlapped with
a peripheral region of the first electrode dielectric film and the support surface
of the dielectric film support member in a plan view, the dielectric non-contact region
is overlapped with an intermediate region of the first electrode dielectric film in
a plan view, and the intermediate region is a region adjacent to a side of the first
electrode conductive film from the peripheral region,
the dielectric film suppression member has conductivity and is set to have the reference
potential, and
the first electrode dielectric film is suppressed by the dielectric film suppression
member from an upper side in the dielectric contact region.
2. The active gas generation apparatus according to claim 1, wherein
the material gas flow space includes:
a material gas buffer space provided on a side of a lower surface of the reference
potential conductor and receiving material gas through the gas flow path;
a slit space provided on a side of a lower surface of the reference potential conductor
and connected to the material gas buffer space; and
a side surface space provided on a side of a side surface of the reference potential
conductor and connected to the slit space so that material gas is introduced into
the discharge space through the material gas buffer space, the slit space, and the
side surface space, and
the slit space is set to be a space in which material gas hardly flows compared with
the material gas buffer space so that material gas temporarily remains in the material
gas buffer space, and then flows into the slit space.
3. The active gas generation apparatus according to claim 1 or 2, wherein
an outer peripheral line of the conductive film opening part of the second electrode
conductive film is defined as an electrode boundary line,
the second electrode constituting part further includes a cover dielectric film covering
the electrode boundary line of the second electrode conductive film in the active
gas buffer space, and the cover dielectric film includes a cover through port passing
through the cover dielectric film in a region overlapped with the dielectric through
port in a plan view,
the active gas generation apparatus further includes:
a shield dielectric film provided in a region overlapped with the dielectric through
port and the cover through port in a plan view on a bottom surface of the active gas
buffer space; and
a gas ejection port provided to pass through the reference potential conductor in
a peripheral region of the shield dielectric film so that the gas ejection port is
overlapped with the cover dielectric film in a plan view and is not overlapped with
the dielectric through port and the cover through port in a plan view,
the discharge space includes an auxiliary discharge space including the dielectric
through port, the cover through port, and a part of the active gas buffer space in
addition to the main discharge space, and
a path from the auxiliary discharge space to the gas ejection port is defined as an
active gas flow path.
4. The active gas generation apparatus according to claim 3, wherein
the chassis bottom part of the chassis includes a chassis opening part in a region
overlapped with the active gas buffer space in a plan view, and active gas ejected
from the gas ejection port is introduced to a lower side through the chassis opening
part, and
the chassis opening part has a tapered shape with a larger opening area with decreasing
distance to a lower side.
5. The active gas generation apparatus according to any one of claims 1 to 4, wherein
the electrode unit includes a plurality of electrode units, and
the chassis bottom part of the chassis includes a cooling path flowing a cooling medium,
and the cooling path is provided on a lower side of the reference potential conductor
of each of the plurality of electrode units.
6. The active gas generation apparatus according to any one of claims 1 to 4, wherein
an upper surface of the first electrode conductive film and a lower surface of the
first electrode dielectric film have a contact relationship with each other via a
solution having conductivity,
the first electrode conductive film is a power supply body,
the power supply body includes:
a cooling medium flow path provided in an inner portion to flow a cooling medium;
a cooling medium inlet for receiving a cooling medium from an outer portion and supplying
the cooling medium to the cooling medium flow path; and
a cooling medium outlet for exhausting a cooling medium flowing the cooling medium
flow path to an outer portion,
the active gas generation apparatus includes:
an alternating-current power source applying the alternating-current voltage; and
first and second current introduction members each having conductivity and receiving
the alternating-current voltage, each of the first and second current introduction
members including a conduction pipe which can transport the cooling medium,
the first current introduction member has an electrical connection relationship with
the power supply body, and is connected to the power supply body to be able to supply
the cooling medium from the cooling medium inlet to the cooling medium flow path through
the conduction pipe, and
the second current introduction member has an electrical connection relationship with
the power supply body, and is connected to the power supply body to be able to exhaust
the cooling medium from the cooling medium outlet to an outer portion through the
conduction pipe.
7. The active gas generation apparatus according to claim 6, wherein
the electrode unit includes first and second electrode units,
the cooling medium flow path, the cooling medium inlet, and the cooling medium outlet
of the first electrode unit are defined as a first cooling medium flow path, a first
cooling medium inlet, and a first cooling medium outlet, respectively,
the cooling medium flow path, the cooling medium inlet, and the cooling medium outlet
of the second electrode unit are defined as a second cooling medium flow path, a second
cooling medium inlet, and a second cooling medium outlet, respectively,
the active gas generation apparatus further includes:
a cooling medium relay member having conductivity, and including a relay cooling medium
flow path provided in an inner portion and first and second through flow paths each
provided to pass through a lower surface from an upper surface of the cooling medium
relay member; and
first to fourth relay conduction pipes each having conductivity and each having a
cooling medium transportation function,
the first to fourth relay conduction pipes are disposed between the cooling medium
relay member and the power supply body of each of the first and second electrode units
to satisfy first to fourth cooling medium flow conditions,
the first cooling medium flow condition is a condition that the cooling medium flows
between the first current introduction member and the first cooling medium inlet through
the first through flow path and the first relay conduction pipe,
the second cooling medium flow condition is a condition that the cooling medium flows
between the first cooling medium outlet and the relay cooling medium flow path through
the second relay conduction pipe,
the third cooling medium flow condition is a condition that the cooling medium flows
between the relay cooling medium flow path and the second cooling medium inlet through
the relay conduction pipe, and
the fourth cooling medium flow condition is a condition that the cooling medium flows
between the second cooling medium outlet and the second current introduction member
through the fourth relay conduction pipe and the second through flow path.
8. The active gas generation apparatus according to claim 6 or 7, wherein
the first electrode dielectric film has a concave-convex structure on an upper surface
which is not overlapped with the power supply body and the dielectric film suppression
member in a plan view.